The AMPA receptor antagonist GYKI 52466 reverses the anti-cataleptic effects of the competitive NMDA receptor antagonist CGP 37849.

The effects of the AMPA receptor antagonist GYKI 52466 (1-(4-aminophenyl)-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine HCl) on haloperidol-induced catalepsy were tested in drug-naive rats and in rats pretreated with the competitive NMDA receptor antagonist CGP 37849 (DL-(E)-2-amino-4-methyl-5-phosphono-3-pentenoic acid). CGP 37849 (4 mg/kg i.p.) given alone significantly reversed haloperidol-induced catalepsy (0.5 mg/kg i.p.) while GYKI 52466 (4.8 mg/kg i.p.) given alone was without effect. Administration of GYKI 52466 to rats pretreated with CGP 37849 abolished the anticataleptic effects of the competitive NMDA receptor antagonist seen following single administration. Thus the AMPA receptor antagonist prevents behavioural effects induced by a NMDA receptor antagonist in this behavioural model.